feat: launch NEXUS TERMINAL — Bloomberg-style FX options analytics platform

Full-stack forex options analytics terminal with Bloomberg-inspired UI.

Backend (FastAPI + Python):
- Garman-Kohlhagen options pricing engine with full Greeks
- Goldman Sachs gs-quant AI signals (RSI, MACD, Bollinger, Hurst, OU)
- Monte Carlo GBM simulation and volatility surface generation
- CFTC COT institutional positioning + Forex Factory economic calendar
- Live data proxy: OpenSky aircraft + USGS earthquakes (CORS-safe)
- Multi-leg strategy library (straddle, iron condor, butterfly, spreads)

Frontend (React 18 + Vite):
- NEXUS animated orbital logo (3-ring SVG) + canvas favicon animation
- Bloomberg terminal design: JetBrains Mono, color-mix() tokens
- 11 dashboard tabs: Greeks, Chart, AI Signals, 3D Surfaces, Breakeven,
  Scenarios, Monte Carlo, Institutional, Calendar, Live Map, Live Feeds
- Live World Map (react-leaflet): aircraft, earthquakes, weather radar
- Live Feeds: CoinGecko crypto top-12 + Windy.com global webcams
- Economic calendar with filters + institutional flow (CFTC COT)
- Animated landing page + session-based routing
- Fully responsive dark-only terminal design system

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/config.py

@@ -0,0 +1,41 @@
+"""
+config.py — Central configuration and default parameters.
+
+Change values here instead of hunting through the codebase.
+"""
+
+# ---------------------------------------------------------------------------
+# Default market parameters
+# ---------------------------------------------------------------------------
+DEFAULT_SPOT: float = 100.0       # Starting underlying price (S₀)
+DEFAULT_VOLATILITY: float = 0.20  # Implied volatility (σ), 20 %
+DEFAULT_RISK_FREE_RATE: float = 0.01  # Annualised risk-free rate (r), 1 %
+DEFAULT_TIME_TO_EXPIRY: float = 0.5   # Time to expiry in years (T)
+
+# ---------------------------------------------------------------------------
+# Surface scan ranges
+# ---------------------------------------------------------------------------
+SPOT_LOW: float = 80.0
+SPOT_HIGH: float = 120.0
+SPOT_STEPS: int = 50
+
+VOL_LOW: float = 0.10
+VOL_HIGH: float = 0.40
+VOL_STEPS: int = 50
+
+# ---------------------------------------------------------------------------
+# Plot settings
+# ---------------------------------------------------------------------------
+FIGURE_SIZE: tuple = (8, 7)
+SAVE_PLOTS: bool = True          # Set False to skip saving PNG files
+PLOT_OUTPUT_DIR: str = "plots"   # Relative to the directory main.py is run from
+
+# ---------------------------------------------------------------------------
+# Example portfolio (list of option legs)
+# Each leg: type ('call'|'put'), K (strike), T (expiry in years), qty (signed)
+# ---------------------------------------------------------------------------
+EXAMPLE_PORTFOLIO: list = [
+    {"type": "call", "K": 100.0, "T": 0.5, "qty": 2},   # Long 2 ATM calls
+    {"type": "put",  "K": 95.0,  "T": 0.5, "qty": -1},  # Short 1 OTM put
+    {"type": "call", "K": 110.0, "T": 0.5, "qty": -1},  # Short 1 OTM call (spread)
+]